Some more news about the Trump administration - the administration's relationship with Turkey, a NATO ally, has taken a turn for the worse. There's a conflict over the fate of an American citizen. He's a Christian pastor who's under house arrest in Turkey. President Trump has imposed sanctions on two Turkish officials who are involved in the case against the pastor. Turkey has said it will retaliate without delay. NPR's Michele Kelemen has the story.

MICHELE KELEMEN, BYLINE: White House Press Secretary Sarah Sanders says President Trump has spoken several times to Turkey's president about Pastor Andrew Brunson.

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SARAH SANDERS: We've seen no evidence that Pastor Brunson has done anything wrong, and we believe he is a victim of unfair and unjust attention by the government of Turkey.

KELEMEN: Brunson, who's from North Carolina, has lived in Turkey for more than two decades. He was arrested along with thousands of others following a failed coup attempt in 2016. He was released from jail only last week, but remains under house arrest.

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SANDERS: At the president's direction, the Department of Treasury is sanctioning Turkey's minister of justice and minister of interior, both of whom played leading roles in the arrest and detention of Pastor Brunson.

KELEMEN: That means any assets they might have in the U.S. will be frozen and Americans can't have dealings with them. Turkey's foreign ministry says the move will damage efforts to resolve bilateral problems. It's accusing the U.S. of disrespectfully intervening in Turkey's judicial system, and it's threatening to retaliate. Secretary of State Mike Pompeo has been in touch with his Turkish counterpart. The State Department is also raising concerns about the cases against three of its locally-hired staff in Turkey.

Meanwhile, at a confirmation hearing yesterday, Senator Jeanne Shaheen asked the man tapped to be assistant secretary of state for political-military affairs, Clarke Cooper, how he would deal with Turkey, a country that buys U.S. planes but also plans to purchase Russian S-400 missiles.

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CLARKE COOPER: Safe to say Turkey is a difficult partner, but they are a partner. They remain a NATO partner. They remain a counterterrorism partner, particularly on combating ISIS. And as you noted, a sale - something like the S-400 - that would be - that would be catastrophic for us.

KELEMEN: Cooper made clear that this is a hard balancing act, pressing Turkey on areas of disagreement while also trying to maintain an important alliance. Michele Kelemen, NPR News, the State Department. Transcript provided by NPR, Copyright NPR.